78211771 has 8 divisors (see below), whose sum is σ = 89812800. Its totient is φ = 67359240.

The previous prime is 78211741. The next prime is 78211789. The reversal of 78211771 is 17711287.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78211771 - 2⁷ = 78211643 is a prime.

It is a super-2 number, since 2×78211771² = 12234162245912882, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78211741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 186901 + ... + 187318.

It is an arithmetic number, because the mean of its divisors is an integer number (11226600).

Almost surely, 2^78211771 is an apocalyptic number.

78211771 is a deficient number, since it is larger than the sum of its proper divisors (11601029).

78211771 is a wasteful number, since it uses less digits than its factorization.

78211771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374249.

The product of its digits is 5488, while the sum is 34.

The square root of 78211771 is about 8843.7419116571. The cubic root of 78211771 is about 427.6521961886.

The spelling of 78211771 in words is "seventy-eight million, two hundred eleven thousand, seven hundred seventy-one".